Acid resisting pump



Oct. 2, 1934. LATHAM 1,975,583

ACID RESISTING PUMP Filed Deo. l5, 1933 3 Sheets-Sheet 1 Oct. 2, 1934. LATHAM ACID RESISTING PUMP Filed Dec. 15, 1933 3 Sheets-Sheet 2 3 W s P o 2 e m A 4 A y 4 w l W T P 9 n W in? Oct. 2, 1934. H.'ILATHAMV 1,975,583

ACID RESISTING PUMP Filed Dec. 15, 1933 3 Sheets-Sheet 3 65 Ill llllh ll 7i H Patented Oct. 2, 1934 UNITED STATES PATENT orrlcr.

2 Claims.

In the use of feed water heaters of the closed type a deposit called scale formed on the inside of the tubes must be removed periodically, and is usually done by pumping a solution of muriatic acid through the tubes. Acid strong enough to remove the scale efficiently, attacks the pump with vigor and the loosened scale forms an abrasive that rapidly wears away the moving parts. As a resut maintenance has been costly.

The principal object of this invention is to provide a pump that will endure this service for long periods and can be cheaply and quickly restored to efliciency.

In general, this is accomplished by using acidproof material for all parts that must be in contact with the acid and so making the parts subject to abrasions that they can be readily replaced.

For example, the pump body and valve casing may be made of lead with removable cages and valveseats also of lead, and the ball valves, the packing, the gaskets and the piston, or diaphragm, may be made of rubber.

The preferred embodiment of the invention is illustrated in the accompanying drawings in which Figs. 1 and 2 are side and end elevations of the pump assembled with the driving motor in a frame;

Fig. 3 is a vertical section through the pump and a portion of the frame, taken on line 3-3 of Fig. 2; V

Fig. 4 is a longitudinal section through one form of piston;

Fig. 5 is a transverse section taken on the line 55 of Fig. 3;

Fig. 6 is a vertical section taken on the line 6-6 of'Fig. 5;

Fig. '7 is a vertical section taken on the line 7-7 of Fig. 5;

Fig. 8 is a horizontal section taken on the line 8- 8 of Fig. 6; and

Figs. 9, 10 and 11 are perspective views of two of the valve cages and a removable valve seat.

But these drawings and the specific description are used for illustration and not for limitation.

Referring now to Fig. 1, the frame includes a bottom plate 10, a top plate 11, four tubular columns 12, and bolts 13 by which the other parts are held securely clamped in position.v

The pump proper is secured to the bottom plate 10 and driven by a motor 14 mounted on the top plate 11 through a crank disk 15 having a crank pin 16 fitted in a crank pin block 17 that slidably engages the forked end 18 of the walking beam 19, fulcrumed at 20 on a fulcrum bracket 21 and pivoted at an intermediate point to a connecting rod 22 that operates the piston.

The pump body comprises a lead cylinder 23 having a square flange 24 (Fig. 5) secured to the 6 bottom plate 10 by bolts 25.

The cylinder'has a long counter bore 26 (Fig. 3) in which is fitted a bronze neck ring 27, a rubber packing 28 and'a bronze packing gland 29. The gland is adjusted by bolts 30 extending through a gland-retaining ring 31, recessed to receive the top of the packing gland, and a gland anchor ring 32 split and fitted in the groove 33 surrounding the cylinder 23.

The valve body 34 is a generally rectangular block of lead having a circular projection 35 ending in a nipple 36 for cooperation with a lateral bore 3'7 at the bottom of the cylinder and a counter bore or machined face 38 surrounding the bore 3'7. A rubber gasket 39 serves to seal the joint between the pump body and the valve body when the clamp 40 is set up properly.

The inlet to the valve body (Fig. 6) is formed by a lateral bore 41 terminating below a vertical bore 42 that forms the inlet valve chamber and has a step 43 near the bottom to receive a removable valve seat 44 oflead for cooperation with the rubber ball 45. The valve seat and rubber ball are maintained in their proper position by a valve cage 46, shown in perspective in Fig. 9, which extends from the top of the valve body 34 to the bottom of the valve chamber, where it has a narrow base 47, resting partly on the valve seat 44 and partly on the stepped bottom of the valve chamber.

The valve cage 46-has a generous ball chamber 48 perforated at 49. From the base 4'? to well above the middle of the height the cage 46 is reduced externally to provide a generous clearance 50 for acid to flow through it. Above this point there is just sufficient clearance 51 to prevent the cage from binding in the valve chamber.

The inlet valve chamber 42 is intersected at one side by a transverse bore 52 (Figs. 7 and 8) stopped with a plug 53 and ending below another vertical bore 54, forming the outlet valve chamber. Like the inlet valve chamber 42, the outlet valve chamber has a stepped bottom 55 fitted with a removable valvev seat 56 of lead cooperating with the rubber ball valve 5'7. This chamber is equipped with an outlet valve cage 58, shown in perspective in Fig. 10, and resembling the inlet valve cage very closely, except that it is much shorter. A comparison of Figures 6 and 7, however, will show that it bears the same relation to the valve chamber, the removable valve seat at one end to receive a stud 68 and a lateral notch at the other end to receive a similar stud 69, which studs and bar form a clamp for the cover.

The inlet and outlet bores 41 and 59 (Figs. 6 and 7) have counter bores 70 and 71, originally surrounded by cylindrical flanges that appear .as conical flanges 72 and 73, grasping the beveled flanges 74 and 75 on short lengths of lead pipe 76 and '77.

In assembly the pipes are inserted into the counter bores after which the flanges are pounded down and calked to make liquid-tight joints.

Each pipe 76 and 77 is fitted with the conventional union 78, by which it is removably connected to a 'short piece of lead pipe 79, attached to a rubber hose 80 leading to the respective openings in the feed water heater.

The base 64 of the air chamber 62 has a neck 81 connected to the top of the valve body by the same means as described in the connection with the pipes 76 and 7'7.

The piston rod 82 (Figs. 3 and 4) has a forked end 83 pivoted to the connecting rod 22, and a threaded end 84 adapted to receive a bronze plate 85 and a bronze nut 86. Between the plate 85 and the forked end 83 is the rubber piston proper 87, preferably made up of a number of disks clamped in place by the nut and washer. After this assembly has been made the lower end is dipped in molten gutta percha and a seal 88 is formed about the metal parts, best shown in Figs. 3 and 4.

For convenience in moving the apparatus about from one locomotive to another, the frame is usually mounted on a suitable truck, not shown.

In operation the hose connections are made, and the motor 14 started, with the result that the walking beam 19 will be rocked about the fulcrum pin 20 and the connecting rod 22 will reciprocate the piston in the :cylinder. As the piston rises the exhaust valve will be urged to the position shown in Fig; 7, while the inlet valve will be raised and the acid will enter the valve chamber passing through the bore 89 (Fig. 3) into the cylinder. On the down stroke of the piston the inlet valve will maintain the position shown in Figs. 3 and 6, the discharge valve will be raised and the acid will pass out through the pipe '77.

When the piston becomes slightly worn, correction can be made by adjusting the bolts 30; after greater wear the piston must be removed and reformed, which can be done by hand. or by chucking it up in a lathe and applying emery cloth, or the like. Upon being reinserted, it is necessary to tighten down the packing gland, comprising the gasket 28, until a proper seal is formed.

When it is necessary to repair or replace any part of the valve structure, loosening one nut will release the cover 66 and permit the valve cages to be quickly lifted out by a suitable tool inserted through the longitudinal bores down to the ball chamber. If a valve seat is to be merely restored it will usually be sufiicient to apply a steel ball in the place of the rubber ball valve and strike it lightly with a hanmier and a drift. If the valve seat is too far gone for repair, it may easily be replaced with a new one.

Valve balls that have become worn out of round, or are too small, are usually replaced by releasing the clamp, removing the cover, extracting the valve cages, inserting new balls and reversing the operation.

In this preferred form the pump body and valve body are made from blocks of lead, bored and fastened with suitable tools, as will be readily understood. And this work is facilitated by making the pump and valve bodies separately and clamping them together, as described.

Lead and hard rubber have been found to make very satisfactory combinations, but many other materials may be used instead. Generally speaking, earthen-ware, glass, and the acid resisting alloys are suitable for the bodies and cages. Hard rubber, and its many substitutes, made from various natural and synthetic gums with fillers, etc., are very suitable as valves and cages. The phenol condensation products, generally known as Bakelite, and its imitations, are sufficiently acid resisting to serve well, although they are rather costly.

I claim as my invention:

1.. In a pump for operating on acids and the like a body of acid resistant material provided with a cylinder and a counterbore, a lining of rubber material in the counterbore, a piston mounted for reciprocation in the cylinder and counterbore, said piston having an outer surface of rubber material whereby the piston may readily be restored to true cylindrical form after a period of use, in combination with a gland bearing on the lining and means for adjusting the gland to vary the effective bore of the cylinder after change in the diameter of the piston.

2. In a pump for operating on acids and the like a body of acid resistant material provided with a cylinder and a counterbore, a lining of rubber material in the counterbore, a piston mounted for reciprocation in the cylinder and counterbore, said piston comprising a rod and a plurality of discs of rubber material secured thereon whereby the piston may readily be restored to true cylindrical form after a period of use, in combination with a gland bearing on the lining and means for adjusting the gland to vary the eifective bore of the cylinder after change in the diameter of the piston.

HENRY LATHAM.

LEO 

